After weeks of waiting, my invite to Google's Project Fi arrived earlier this week. Since I already have a Nexus 6 -- currently the only phone supported by the wireless service -- I ordered the SIM card kit, which arrived today. Even if you don't have a Nexus 6, the $30 kit is worth the money.

I figured that out immediately when the Project Fi box was clearly much larger than needed for a small plastic card. Instead, the box looked big enough to hold an Amazon Echo.

That's because there's a nice welcome kit for the service, which uses the carrier networks of both T-Mobile and Sprint, depending on which is better at a given time and place. Project Fi also supports Wi-Fi calling; you can start a conversation on your home network and the call is advertised as seamlessly transferring over to cellular service as needed. I'll be testing how well that works in the coming days.

In the meantime, I'm impressed by the accessories that are part of the welcome kit. Aside from the SIM card, Google included three extras for my $30.

First is a pair of in-ear headphones and three sizes of rubber cups for proper ear fit. The headphones have a built-in microphone and are hard wired to an audio splitter: Plug them into your phone to hear music, calls or video and a second person can tune in as well.

Next is an external battery with 6,000 mAh capacity. You recharge it with an included USB cable and it should top off most phones two times before running out of juice. A nice touch is a pair of standard USB ports to charge two devices at one time. One of the two ports provides 2.1 Amps of current to quickly recharge phones or tablets that can handle it, while the other is a single Amp power output.

Lastly, Google includes a Project Fi case to cover the back of a Nexus 6. There's nothing really fancy about it and I don't think the plastic back of the Nexus 6 needs to be covered by a plastic case. It does, however, include a flexible and removable bumper for added protection. In theory, you could just use the bumper on a Nexus 6 although it's not super snug.

All in all, the extras are worth the price of admission even if it turns out I don't like or want to use Project Fi service. There's no commitment with Project Fi as Google charges on a month-to-month basis and it's easy to cancel service at any time.

The monthly fee for Project Fi is $20 for unlimited talk and texts plus $10 for each GB of LTE service used. You can choose and pay for as much data as you want -- I went with the minimum to start -- and Google will credit your account for any unused data.

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